I figure out the original issue but got a new one.

In my code, I had Fruit.java looking like this:

package test;

import org.jboss.seam.ScopeType;
import org.jboss.seam.annotations.Name;
import org.jboss.seam.annotations.Scope;
import org.jboss.seam.annotations.remoting.WebRemote;

@Name("fruit")
@Scope(ScopeType.EVENT)
public class Fruit {

     private long fruitId;
     private String name;
     
     @WebRemote
     public long getId() {
          return fruitId;
     }
     @WebRemote
     public void setId(long id) {
          this.fruitId = id;
     }
     @WebRemote
     public String getName() {
          return name;
     }
     @WebRemote
     public void setName(String name) {
          this.name = name;
     }
     
}

It looks like Seam was looking for the member variable instead of the bean property through getter/setter.  So it found fruitId, instead of id.  

I'm not getting the exception once I changed the fruitId to just id.  However, the value is not getting passed in.

Here's the rest of the code pieces:

FruitAdmin:

package test;
import javax.ejb.Local;
import org.jboss.seam.annotations.remoting.WebRemote;
@Local
public interface FruitAdmin {
     @WebRemote
     public void save(Fruit fruit);
}

FruitAdminBean:

package test;

import javax.ejb.Stateless;

import org.jboss.seam.annotations.Logger;
import org.jboss.seam.annotations.Name;
import org.jboss.seam.log.Log;

@Stateless
@Name("fruitAdmin")
public class FruitAdminBean implements FruitAdmin {

     @Logger Log log;
     
     public void save(Fruit fruit) {
          log.info("getting this fruit id: #0, name #1",fruit.getId(),fruit.getName());
     }

}

and finally, the xhtml:

<!DOCTYPE composition PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" 
                             "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

<ui:composition xmlns="http://www.w3.org/1999/xhtml"
                xmlns:s="http://jboss.com/products/seam/taglib"
                xmlns:ui="http://java.sun.com/jsf/facelets"
                xmlns:f="http://java.sun.com/jsf/core"
                xmlns:h="http://java.sun.com/jsf/html"
                xmlns:rich="http://richfaces.org/rich"
                template="/layout/template.xhtml">
                       
<ui:define name="body">
    
<s:remote include="fruitAdmin,fruit"/> 

<script type="text/javascript">

function createNewFruit() {

     var fruitAdmin = Seam.Component.getInstance('fruitAdmin');
     var newFruit = Seam.Component.newInstance('fruit');
     newFruit.id=1234;
     newFruit.name = "mango";
     newFruit.justNumber = 56778;
     newFruit.justString = "orange";
     
     fruitAdmin.save(newFruit);
     
}

createNewFruit();

</script>


</ui:define>

</ui:composition>

Forgot to mention that when ran, the admin bean produces this output:

INFO  [FruitAdminBean] getting this fruit id: 0, name mango

I also tried changing from long to Long and got a null instead of 0.